Forming caps, closures, and the like



June 8, 1948. J. w. THOMAS FORMI ING CAPS, CLOSURES, AND ,THE LIKE Filed Sept. 15, 1944 4 Sheets-Sheet 1 INVENTOR. film W Thomas Illnu ///1 v anon/v5) J. W. THOMAS FORMING CAPS, CLOSUREQ, AND THE LIKE June 8, 1948.

4 Sheets -Sheet 2 Filed Sept. 15, 1944 2 4 Va w w mm h m ma II .252 V k W Mr 7, W \quk... 55. m n 4 v M I \I M W 4 2 4 F a 6 v W M Z Z W Z W 0 0 1 m swim v J. w. THOMAS FORMING CAPS', CLbSURES, AND THE LIKE June 8, 1948.

Filed se i. 15, 1944 4 Sheets-Sheet 3 I INVENTOR.

. Mm iii/Mm HTTOlP/VE Y June s, 1948. w, T OMAS 2,442,965

FORMING CAPS, CLOSURES, AND THE LIKE Filed Se t. 15, 1944 4 Sheets-Sheet 4 v l 75 l i 64 79 I I j e9 I I. 75' 76 W57 74 77 5 5a 71 j v 72 /70 mmvroa Jdfiiz l3. Tjzamas I W; HTTORNE'Y Patented June 8, 1948 UNIED STATES TENT OFFICE 12 Claims. 1

This invention relates to the making of seals or closures for containers, and particularly the die-shaping of a closure member to provide beading, threading and the like. Y The object of the invention is to provide the desired configuration of the closure by successive die-shaping operations on a blank of generally annular form.

Further objects of the invention particularly in the provision of dies gripping and shaping the closure in a series of steps will appear from the following specification taken in connection with the accompanying. drawings in which Fig. 1 is an elevational View with parts in section of die means receiving the closureblank for the first operation;

Fig. 2 is a sectional plan view of the lower die taken on line 22 of Fig. 1;

Fig. 3 is a partial sectional. elevation of the lower die of Fig. 1 operated to internally grip the closure blank;

Fig. 4 is a sectional elevation of the two dies of Fig. 1 partially operated to begin the formation of a head on the upper edge of the closure blank;

Fig. 5 is a sectional elevation of the dies of gig. I in position completing the formation of'the ead;

Fig. 6 is a sectional elevation of die means receiving the beaded closure blank for the second operation to form the threading;

Fig. '7 is a partial sectional plan View of the lower die taken on line 11 of Fig". 6;

Fig. 8 is a sectional elevation of the threading dies moved to grip the beaded blank and ready for the threading operation;

v Fig. 9 is a similar view with the dies completing the threading of the closure; and

Fig. 10 is a sectional view on enlarged scale of the closure and the cooperating threading die surfaces. Y I The particular seal or closure shown in the drawings is a ring or band B of paper or cardboard impregnated with thermoplastic material, such for instance as parafiin. The closure is termed in two operations, the first pressing a bead on one edge of the band and the second pressing threads into the remainder of the band. 4 The shaping dies comprise an upper formin head I4 and the base l5 carrying the closure blank B. The base comprises a cylindrical body [5 fixed in place. on platen H by bracket I8 and threading l9. Within the cylinder It slides a plunger 20 supported and operated by the rod 20a and carrying at its upper end the frusto conical member,

2| around which are grouped the segments 22 of die ring 23 expanded by relative upward movement of member 2| and resiliently contracted by the spring 24 of circumferential pring ring'25.

5 In the initial position of the dies (Fig, 1); the

' closure wank B rests on the'segnient 2 5i spr n ring 25 with the upper ends 2 or segments 22 loosely.po sitioned within the'lower portion of the blank. The segments '22 rest in recess 49L of the cylinder 1 s, and as rod 21m, plunger 20 an e'omeai member 2| rise, the segments 22am moved upward and outward to be lifted fromthe recess 29 of cylindrical body [6 and e'X'pan'dedinto contact with the timer surface at the solid retaining ring 30, 'simult anecu'sly expandingrin'g 25 and bringing ends 21 6f the segments into enga ement with the inner surfaces of blank B to securely hold it as shown in Fig. 3. 1

The internal of the segment ends 2] confined to the lower portion or the band B, leaving the upper part free for the beading'operation by the tanning segments 32 of the upper head [4 as this head is moved downward or the base i5 is moi/ea upward to cum the upper edge of the closure blank inward as shdwn'm Figs 4 and5.

The head It comprises th block po tion 33 having shank 34 threaded in the end of the shaft 35 fitted into sleeve is. The meek 35 has'the tapered recess 31 fitted with thefor'ming' segments 32 held in the recess by s'tud38 and retainer 39. The annular grcove' ll recess 4!! of the members 32 progressively turns the edge of the closure inward as thgemsgure is forced 'intolth'e recess and groove (Fig. i). The curling of the bead 43 on the closure is completed by the'ar'cuate surfaces 44 of the segments 22 tvhen the upper ends of these sgl" ents engagetne bottom 45 of recess 10 (Fig. 5) at the end of the relative movement between the head andthe base. v The upper forming member ismade in segments 32"sirriilar to other parts ofthe device, and the position shown in I'is assured by'the weight of the segments the ap red sea of stud 38, In this position thjebore of recess 45 in is slightly larger than the outside diameter of heees f e' pa were: the edge of band B comes in contact with annular groove M (Fig. 4), raising the segments 3 2 until they touch the surface at the top of re'cejss 3] (Fig. 5). The segments 32 are forcedinward by the tapered surface 310. of the recess 31, thus reducing the diameter of recess to the'giut'side diameter of band B. After the curling operation has been completed (Fig. 5) and as the base 15 band B. When the 5 recedes, the segments 32 will assume the position 3 shown in Fig. 1, in which they are expanded by the stud 38, which assures that the band will not stick in the recess 45 and will be gripped by segment ends 2'! so that the formed band is always found on the lower head.

In order to produce a satisfactory head on the paper band B, the apparatus is maintained at a temperature sufficiently high to render the thermoplastic material of the band somewhat soft. Heating elements are, therefore, provided as shown at 60 around the upper portion of the cylindrical body l6, and similar elements may also be included in the head l4, for instance as shown at 83 in the head 64 (Figs. 6, 8 and 9).

Upon completion of the bead the relative movement of the parts is reversed and the base I5 is withdrawn from the head I4. As the segments 22 move downward into their seat 29 in member |6 the conical expander 2| withdraws downward from these segments permitting them to contract under the action of the spring 24 disengaging their upper ends 21 from the beaded blank and permitting its easy removal.

The movements of the die parts are precise and accurately guided. The block 20 fits closely in cylinder l6 and the lower portion 45 of conical member 2| is centered and tightly held in recess 41 of the block 20. Segments 22 are positioned and guided on conical member 2| by keys 48 set in member 2| and sliding in keyways 49 in the segments.

The band is thus accurately held, softened and beaded with the curl or bead facing inward as shown, the closure then being ready for the following operation forming the threads by a separate die mechanism.

This thread forming mechanism comprises a plunger 50 on rod 50a and having an upper recess 17 fitting the lower portion 16 of conical member 5| carrying the die segments 52 sliding on the conical member and resiliently contracted thereon by the annular spring 54. The upper ends 5'! of these segments have their peripheral portions formed with threads 58 and the lower portions of the segments 52 are seated in reces 59 of cylindrical member 62 fixed in stationary bracket arm 63 and serving as a guide for the block 55 slidingly fitted within the cylinder.

The upper die mechanism is carried on head 64 on plunger 65 fixed n the end of rod 66 vertically sliding in sleeve 67. The head comprises an outer housing 69, slidably keyed to the plunger 65 and carrying the annular retainer ring 10 on the upper surface of which the die segments H are mounted having radial keyways l2 fitted to keys 13 set in the ring. A top plate 14 is supported in place from the housing 69 by stud 15 as shown and springs 16 (one for each segment) between the plate 14 and segments 1| resiliently press the segments outward and hold their inclined peripheral surfaces i1 against the correspondingly inclined surfaces 18 of wedge ring plate 19 fixed to the end of plunger 65 as shown.

The beaded band B from the first operation is placed on the die heads 51 as shown (Fig. 6). As the rod 50a and plunger 55 move upward, the conical member expands the die segments 52 against the tension of the spring ring 54 until the threads 58 of the end segments 51 engage the inner surfaces of the band B (Fig. 8). As these base parts continue to move upwardly, the surfaces 80 of segments 52 engage the under surface of ring (Fig. 9) moving the housing 69 upward on shaft or plunger 65. This forces the die segments 1| upward with the base parts and drives 4 the segments inward as the segment surfaces 11 ride up on the wedge surface 18 held against upward movement by the plunger 65.

The inner ends of segments have a threaded configuration 8| corresponding to the threading 58 of the segments 52, 51, and the contraction of outer die segments H and expansion of the inner die segments 52 press the threads into the paper band B as shown on enlarged scale in Fig. 10.

When the threading of the closure band B has been completed, the base parts are moved downward and the housing 69 follows this movement for a short distance and until the housing rests again on the wedge ring plate 19. Springs 16 during the downward movement force the segments outward withdrawing the die surfaces from the threaded band B, and continuation of thedownward movement of the base parts lowers the segments 52, 51 to seat 59 and permits the segments to contract under tension of spring 54 so that the formed band may be easily removed from the machine.

These thread forming dies are also kept at a temperature sufficientl high to render the thermoplastic material of the band soft and moldable, heating elements 82, 83 being shown in the base and head respectively.

In this apparatus the parts are accurately centered and related in their operation. A bolt 84 fastens conical member 5| to block 50, and keys 85 in member 5| position and guide the segments 52. Over-expansion of segments 52 is prevented by engagement of their lower surfaces against the end of block 50 (Figs. 8 and 9).

In each operation the closure blank is easily slipped over the internal segmental dies which upon their expansion precisely center the blank and internally grip it in centered position. No outer support is required. The internally gripped closure is then engaged by the die surfaces of the cooperating head and the bead or threading formed under a continuation of the simple relative movement between the base and head.

The internal segmental gripping dies are carried upward by their conical expanding member, and these dies in turn carry the closure blank with them throughout the operation. The relative movement between the base and head also effects the die forming operation curling over the bead 43 orshaping the threads between the inner and outer die surfaces by this relative movement and without rotation of the base or head.

The initial beading of the closure with the blank in cylindrical form permits the clamping pressure to be applied without distortion of previously formed flanges, threading or the like, and this beading does not interfere with the subsequent threading of the'blank and is not affected by it.

In the specific mechanism shown illustrating the invention, the spring means contracting the segments is of sumcient resilience to permit expansion of the segmental die into contact with the closure blank by the downward pull of gravity on these parts as the segments leave the seat 29, 59. This limits the initially applied gripping force to an amount which cannot be greater than that required to retain the segments from sliding further down on the conical member, allowing also for the contracting force of the surrounding spring. The segments thus automatically and safely limit the initial clamping pressure at each operation and, except as restricted by engagement of the dies with the aeaaoos blank, the outermost extent of'the expansion of the die segments is determined by the stopping of the segments againstthe ring 30"01 against the end of the die block 20, 50, as the case may be. The final die-shaping operation bringing the segments 22, 52 into contact with the under surface of the head at 45, "I'll develops a reaction tending to force the segments against the "conical members 2|, 5| holding them snugly against any yielding to the die pressures.

Any desired mechanism may be used for relative movement of the base and head, and no movement need be imparted to the head, Yielding means may be employed to limit the forces applied between the base and head, and various modifications of details of the mechanism may be resorted to without departing from the-scope of the invention as set forth in the appended claims.

Iclaim:

1. The method of die-shaping a cylindrical blank comprising gripping the blank internally with expanding pressure without exterior radial support of the gripped area, supporting the blank axially at one edge while maintaining said grip, die-shaping the opposite edge to form a bead thereon, releasing the beaded blank and supporting it by engagement of said bead, gripping the blank internally with expanding pressure without exterior radial support at the gripped area, and die-shaping the blank by external inwardly directed pressure at the area of internal expanding pressure.

2. Die-shaping apparatus for caps, closures and the like comprising a base mechanism having a central longitudinally movable conical member, a plurality of radially expansible and contractible segments carried by said member and longitudinally movable with respect to said member and adapted to receive a closure blank, and resilient means holding said segments against the conical surface of said member, and a cooperating head mechanism having die surfaces adapted to shape said blank supported by said segments of said base mechanism, said apparatus having means for relatively moving said base with respect to said head to complete the die-shaping of said blank.

3. Die-shaping apparatus for caps, closures and the like comprising a vertically movable upwardly directed conical member, a segmental die slidably supported by the conical surface of said member so as to move vertically therewith and relatively thereto and adapted to be lifted and expanded by upward movement of said member from a lower retracted position, a, stop member engaging and positioning said die in said retracted position, means for supporting an annular blank in position to be gripped internally by the expansion of the segments of said die, and a cooperating upper die head shaping said blank during its movement with said die.

4. Die-shaping apparatus for caps, closures and the like comprising a vertically movable upwardly directed conical member, a segmental die slidably supported by the conical surface of said member so as to move vertically therewith and relatively thereto and adapted to be lifted and expanded by upward movement of said member from a lower retracted position, a stop member engaging and positioning said die in said retracted position, means for supporting an annular blank on said die in position to be gripped internally by the expansion of the se ments of said die, and a cooperating upper die head shaping said blank during its movement with said die.

-5. Die-shaping apparatus for caps, closures and the like comprising a vertically movable upwardly directed conical member, a segmental d'ieslidably carried by said member so as to move therewith and relatively thereto and adapted to be expanded by upward movement of said member from a lower retracted position, means i-miting said expansion so that said member and die move vertically upward together, means for supporting an annular blank on said die'in position to'first move vertically with said die and then be internally gripped by the expan'si'on of the segments thereof, and a cooperating upper die head'shaping said blank during its further movement with said die.

6. Dias-haping apparatus for caps, closures and the like comprising a vertically movable upwardly directed conic-al member, a segmental die slidably supported by the conical surface of said'member so as to move vertically therewith and relatively thereto and adapted to be lifted and expandedby upward movement of said member from a lower retracted position, means restricting the amount of movement between the die segments and the conical member so as to restrict the expanding movement of said segments, means for supporting an annular blank in position to be gripped internally by the expansion of the segments of said die, and a cooperating upper die head shaping said blank during its movement with said die.

7. Die-shaping apparatus for caps, closures and the like comprising a vertically movable upwardly directed'conical member, a segmental die slidably supported by the conical surface of said member so as to move vertically therewith and relatively thereto and adapted to be lifted and expanded by upward movement of said member from a lower retracted position, means for supporting an annular blank in position to be gripped internally by the expansion of the segments of said die, a cooperating upper die head shaping said blank during its movement with said die, means moving said conical member and segmental die downward, and means for limiting the downward movement of the die segments while permitting continued downward movement of the conical member so as to permit contraction of the die segments to release the formed blank.

8. Die-shaping apparatus for caps, closures and the like comprising a vertically movable conical member, a segmental die carried vertically thereby and expanded by relative movement between the member and the die, and a ring member surrounding the die segments and moving therewith and limiting their expanding movement to a predetermined amount, said segments being adapted to engage and support an annular blank, and a cooperating head having die-shaping surfaces operable to form said blank supported by said segments retained against expansion by said ring member.

9. Die-shaping apparatus for caps, closures and the like comprising a, shaping head adapted to engage the blank to form it, and a support and a cooperating relatively movable base structure having a longitudinally reciprocable conical member, an expansible segmental die seating on said support and movable longitudinally therefrom by said conical member, a spring ring resiliently contracting the segments of said die on said member and engaging the end of said blank to support it in position on said die.

10. Apparatus for forming a bead on an annular blank comprising a vertically movable conical member, a segmental die carried thereby and slidable thereon and adapted to grip and support said annular blank and having upper surfaces adapted to complete the beading of the blank, and a cooperating head having a beading groove adapted to engage the exposed edge of said annular blank and partially form a bead thereon, said bead being completed by engagement of said die surfaces with said partially formed bead.

11. Die-shaping apparatus for caps, closures and the like comprising a vertically movable base structure adapted to internally engage an annular blank, a cooperating head structure comprising a movable housing carrying a plurality of forming dies, a relatively fixed wedge member in said housing engaging said dies, and means on said base structure moving to engage said housing to shift it relative to said wedge member and force said dies inward to shape said blank.

12. Apparatus for die-shaping an annular blank comprising a base having a vertically movable conical member, a segmental die supported on said conical member and adapted to be expanded to grip said blank by vertical movement of said REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 859,977 Rigby 1- July 16, 1907 1,133,424 Beadle Mar. 30, 1915 1,401,132 Bond Dec. 27, 1921 1,765,756 Burger June 24, 1930 2,227,524 Williams Jan. 7, 1941 2,256,124 Moeller Sept. 16, 1941 2,292,054 Cleveland Aug. 4, 1942, 

